Future Trunks Sword Theory

Future Trunks timeline was much different than the current Z one. But still, many of the events that occured when trunks was little, could’ve still happened.

The Majin Boo event with Babadi could’ve still almost happened. Babadi and Dabura comes to Earth, but unlike their counterpart versions in Trunks timeline they would see that most of the Earth’s population would be gone cus of the Androids. So they wouldn’t bother to remain on the planet, since their goal was to gather enough energy to revive Boo. Trunks would be 8 years old around this time.

The Tapion movie happened right after Majin Boo saga because Goku and Vegeta are alive and Gohan knows the mystic form.
Hoi would come to Earth searching for the Dragonballs but Bulma would tell him that they can’t be used anymore.

Hoi could’ve bribed bulma by saying that a great hero in the music box would be able to defeat the Androids, being guilable and wanting a better future she would probably analyze and some how open the box with technology. (Dont tell me it can be done she invented a time machine for gods sake)

The same events would occur with Tapion becoming a brotherly figure torwards Trunks. And when Hirudegan was summoned Future Gohan would try to battle the monster only to be easily defeated and almost killed. Tapion would tell Trunks to kill him with the sword like he did in he present. Trunks, living a life of cruelty and death would take Tapion’s request and keep his sword as a momento, leaving the beast Hirudegan to be lost in the void forever.

It would fit in perfectly because Trunks would be 8 at this time and the history of trunks movie doesn’t happen until Trunks is about 12 or 13.